• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.303-308
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• 1998

Influence of amylose content on formation and characteristics of enzyme-resistant starch (RS) was investigated by scanning electron microscopy, X-ray diffractometry and differential scanning calorimetry. RS yield increased up to 36.1 % as the amylose content of corn starch increased. Starch granules of Amyulomaize V and Ⅶ were more rounded and smaller than those of regular corn ; some were elongated and had appendages. After autoclaving -cooling cycles, the granular structure disappeared and a continous spongy-like porous network was visible in regular corn starch ; the granular structure was stillevident in parts in Amylomaize V and Ⅶ starches. In all isolated RS residues , the porous structures were no longer visible and more compact formations predominated. While regular corn starch showed an A-type X-ray profile, Amylomaize V and Ⅶ starches exhibited a combination of B- and V-types. Regular corn starch lost most of its crystallinity during autoclaving , but the crystallinity was still left in Amylomaize starches as diffuse or poor B-types. All RS residues showed the presence of poor B-type regardless of amylose contents. Transition temperatures and enthalypy of native starches were a little higher in Amylomaize V and Ⅶ starches than those of regular corn starch . Regardless of amylose contents, all RS residues exhibited an endothermic transition over a similar temperature range (135 $^{\circ}C$~169$^{\circ}C$), with a mean peak temperature of ~154$^{\circ}C$, which is generally foud for retrograded amylose crystallities. Higher transition temperature, enthalypy, and RS yield of AMylomaize V and Ⅶ starches were related granular stability shown by the microscopic and crystallographic studies.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.301-303
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• 2005

Effort of rice resistant starch (RS) content on glucose blood level of normal Subject was examined using Suwon 464 and Ilpum, haying different RS contents. Enzymatic-gravimetric method showed RS contents of Suwon 464 and Ilpum were 16.3 and 0.7%, respectively. Both rice varieties, each containing 50g carbohydrate, were pressure-cooked and fed to ten healthy male volunteers after overnight fast. Significant difference was observed in 60 min blood glucose levels of Suwon 464 and Ilpum after meal, showing $90.3{\pm}4.8$ and $111.6{\pm}2.7mg/dl$, respectively (p<0.01).

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.532-538
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• 2006

Physicochemical and sensory characteristics of the jelly prepared with various levels of resistant starch were investigated in this study. Water content of RS10 sample group had significantly the highest value of 12.55% and that of the RS20 sample group had significantly the lowest value of all (p<0.05). RS20 sample group had significantly the highest value in sweetness. The value of pH were decreased with increased levels of the resistant starch in jelly preparation. The Hunter L values were not significantly different among the sample groups, but the RS20 sample group had the highest value of all. The hardness was increased as the addition levels of the resistant starch was increased. Results of sensory characteristics of RS20 sample group showed significantly the higher values in strawberry aroma, sweetness and after taste and significantly the lower value in stickiness than those in the other sample groups at p<0.05. Strawberry flavor, springiness and glossiness of RS5 sample group had significantly the largest values of all (p<0.05). The sensory properties of clarity and glossiness were negatively correlated with the mechanical properties of the color value and hardness at p<0.05. Sensory sweetness and after taste showed negative correlation with the values of pH in jelly preparation(p<0.05).

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.339-347
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• 2011

Flour and isolated starch from chickpea (desi type, 328S-8) were evaluated for their in vitro digestibility and physicochemical properties. The protein content, total starch content and apparent amylose content of chickpea flour and isolated starch were 22.2% and 0.6%, 45.8% and 91.5%, and 11.7% and 35.4%, respectively. Chickpea starch granules had an oval to round shape with a smooth surface. The X-ray diffraction pattern of chickpea starch was of the C-type and relative crystallinity was 24.6%. Chickpea starch had only a single endothermic transition (13.3 J/g) in the DSC thermogram, whereas chickpea flour showed two separate endothermic transitions corresponding to starch gelatinization (5.1 J/g) and disruption of the amylose-lipid complex (0.7 J/g). The chickpea flour had a significantly lower pasting viscosity without breakdown due to low starch content and interference of other components. The chickpea starch exhibited significant high setback in the viscogram. The average branch chain length, proportion of short branch chain (DP 6~12), and long branch chains (DP${\geq}$37) of isolated chickpea starch were 20.1, 20.9% and 9.2%, respectively. The rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents of chickpea flour and starch were 9.9% and 21.5%, 28.7% and 57.7%, and 7.1% and 9.3%, respectively. The expected glycemic index (eGI) of chickpea flour (39.5), based on the hydrolysis index, was substantially lower than that of isolated chickpea starch (69.2).

• Korean journal of food and cookery science
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• v.15 no.4
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• pp.418-425
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• 1999

The characteristics and yield of resistnat starch (RS) in waxy starches which were treated with 0.1N HCl were investigated. Hydrolysis rate of waxy starches were 0.32-0.88%. The yields of RS in waxy maize and waxy barley starches increased with acid treatment time up to 12hr and then decreased. The yield of RS in waxy rice starches increased with acid treatment up to 8hr and then decreased. The hydrolysis and yield of RS were different depending upon the varieties of starch source. Autoclaved normal maize starch showed a gel-like structure, but autoclaved normal maize starch showed crystal particle on the surface by SEM. The shape of autoclaved resistant starch was not different from acid treated ones. X-ray diffraction patterns of native and acid treated starches were all A-types. X-ray diffraction patterns of autoclaved waxy maize starches showed amorphous structures, however, those of RS showed all completely crystalline structure.

• Food Science and Industry
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• v.52 no.4
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• pp.358-374
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• 2019

Indigestible carbohydrates as dietary fiber have attracted interest of consumers due to their several physiological benefits. Recent definitions of dietary fiber have included other indigestible carbohydrates such as resistant starch and resistant maltodextrins, which are natural, colorless, odorless and tasteless low-calorie food ingredients. Unlike some carbohydrates and digestible starches, indigestible starch and maltodextrin resist enzymatic hydrolysis in the upper gastrointestinal tract, resulting in little or no direct glucose absorption. In addition, there is increased microbial fermentation production of short-chain fatty acids in the large intestine. As an emerging functional low-calorie food ingredient, resistant starch and maltodextrin have been shown to have equivalent or superior impacts on human health compared to conventional fiber-enriched food ingredients. In this paper, the definition, strategies to enhance dietary fiber content in foods, some potential health benefits, and applications in food industry for indigestible starch and maltodextrin are summarized and discussed.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.133-138
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• 2002

To examine the cholesterol-towering effects of extruded products made with cassava starch (CS) and blends of cassava starch with either resistant starch (CS-RS) or oat fiber (CS-OF) hamsters were fed with diets containing a high-cholesterol (2%) and high-fat (17%) diet for 20 days. Hamsters fed with a diet containing no cholesterol were used as a control. Total cholesterol (TC) levels in the CS-RS and CS-OF groups were significantly (p>0.05) lower compared to the CS group by 11.5% and 8.5%, respectively. Also, the diets containing fibers decreased the value of low-density lipoproteins plus very low-density lipoproteins fraction by 32.4% (CS-RS diet) and 51.7% (CS-OF), respectively, as compared to the CS diet. Total lipid values were significantly (p<0.05) lower in hamsters fed the CS-RS diet (916 mg/dL) and CS-OF diet (964 mg/dL) as compared to those fed the CS diet (1661 mg/dL). The results obtained in this study suggest that extruded products containing cassava starch blended with either resistant starch or oat fleer, could prevent health problems associated with high levels of cholesterol and hypertriglyceridemia induced by a high cholesterol and fat diet.

• Korean Journal of Human Ecology
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• v.6 no.2
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• pp.49-56
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• 2003

The effects of cooking methods on the total dietary fiber(TDF) and enzyme-resistant starch(RS) contents of nonwaxy and waxy milled and brown rices were investigated. The TDF contents of raw rices were 3.77% for nonwaxy brown, 3.41% for waxy brown, 1.37% for nonwaxy milled and 1.14% for waxy milled rices. The TDF contents were higher in brown rices than milled ones and slightly higher in nonwaxy than waxy ones. However, there were no significant differences among raw and cooked rices with. automatic electric cooker and automatic pressure cooker. The TDF contents of cooked rices did not show any increase, but that of waxy milled ones rather slightly decreased by cooking. The RS contents analysed were not significantly different between automatic electric cooking and automatic pressure cooking. The RS contents of cooked rices were 0.05∼0.06% for nonwaxy milled, 0.09∼0.12% for nonwaxy brown, 0.07∼0.08% for waxy milled, 0.11∼0.13% for waxy brown, which showed higher RS content in brown than milled ones, and in waxy than nonwaxy ones. The ratios of RS/TDF were 4.1∼4.2% for nonwaxy milled, 2.8% for nonwaxy brown, 7.5∼8.9% for waxy milled, 3.6∼3.7% for waxy brown, which showed that the higher the TDF contents, the less the contribution of RS to the TDF.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.508-513
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• 1997

Thermal characteristics and granular morphology on enzyme-resistant starches (RS) formed during heat-moisture treatment (HMT) and retrogradation were investigated in high amylose corn starches, Hylon V and Hylon VII. With each treatment, both starches showed a similar trend in the increase of RS, but RS yield of Hylon VII is higher than that of Hylon V. Specially, RS was increased remarkably by HMT. It was more than doubled from 11.4% to 26.6% for Hylon V and from 15.9% to 32.8% for Hylon VII. A small increase of RS resulted from retrogradation. HMT on starch increased gelatinization temperature, decreased enthalpy. Retrograded starch exhibited small three endothermic transitions at $94^{\circ}C$, $110^{\circ}C$ and $140^{\circ}C$ in differential scanning calorimetry (DSC) thermogram due to the remained ungelatinized starch granules, dissociation of amylose-lipid complex and melting of recrystallized amylose, respectively. Enzyme-resistant starches isolated from native and heat-moisture treated starches showed a broad endothermic transition at higher temperature than native starch, while retrograded starch exhibited a very sharp peak at ${\sim}150^{\circ}C$ due to the melting of amylose crystallites. Under microscopy, starch granules with HMT was not changed, but retrograded starches showed the aggregates of starch granules because amylose leached out during gelatinization. Iodine stained RS clearly showed the differences in enzyme hydrolysis on the native, heat-moisture treated and retrograded starches.

• Food Science and Preservation
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• v.19 no.2
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• pp.216-222
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• 2012

The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature $40-60^{\circ}C$, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at $50^{\circ}C$ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and $50^{\circ}C$ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH 1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.